SH波在界面孔上散射的远场解

Far field solution to SH-wave scattered by an interface cavity

采用Green函数和复变函数方法研究了界面上任意形柱状孔洞对SH波散射的远场解。取含有任意形凹陷的弹性半空间,在其水平表面上任意一点承受时间谐和的反平面线源荷载作用时的位移解作为Green函数,按"契合"的方式构造出两种不同介质交界面上任意形孔洞对SH波的散射模型,利用Green函数建立求解问题的第一类Fredholm积分方程组,求解散射波的远场位移模式和散射截面。通过算例,分析了不同材料组合情况下界面椭圆孔和方孔对SH波散射的远场特性。

The far field solution to SH-wave scattered by an arbitrary shape cavity on an interface was investigated with the methods of Green＇s function and complex function.A suitable Green＇s function was constructed,it was the fundamental solution to displacement field for an elastic half space with any cavity under anti-plane harmonic line source loading exerted at an arbitrary point on its horizontal surface.The model of SH-wave scattered by a cavity on the interface of two different media could be built based on the idea of conjunction.Then a series of the first kind of Fredholm integral equations for determining the displacement mode of scattered wave in far field and scattering cross-section were set up using Green＇s function.The numerical examples were given and the far-field characteristics of SH wave scattered by an elliptical cavity and a quadrate one under different media combinations were analyzed.